E-Math is where careless slips cost grades.

O-Level E-Math · Paper 2 · Question 7 (excerpt)

Twenty-four mark deductions follow. Each represents one mark lost on a standard E-Math paper to a presentation or convention error rather than a knowledge gap. The total comes to negative twenty-four marks.

1. −1Used degrees in the arc length formula.(a)
2. −1Forgot the unit “cm” on the final answer.(a)
3. −1Wrote 14.4 instead of 14.4 cm — examiner can’t assume.(a)
4. −1Used ½·a·b·sin C with C in degrees, not radians.(b)
5. −1Computed sector area but forgot to subtract the triangle.(b)
6. −1Rounded sin(1.2) to 0.93 before final calculation.(b)
7. −1Gave the final area in 2 sig fig where 3 was required.(b)
8. −1Forgot the unit “cm²” on the area answer.(b)
9. −1Wrote workings without the “Area =” label.(b)
10. −1Used Pythagoras’ theorem instead of the cosine rule for BC.(c)
11. −1Computed BC² correctly but forgot to take the square root.(c)
12. −1Added three lengths but missed the OA segment entirely.(c)
13. −1Final perimeter not given in 3 significant figures.(c)
14. −1No units on the perimeter answer.(c)
15. −1Multiplied cost per cm² by area in cm — unit mismatch.(d)
16. −1Forgot to round the cost to the nearest dollar.(d)
17. −1Wrote the dollar symbol after the number, not before.(d)
18. −1No final answer statement — just a bare number on the line.(d)
19. −1Working written in pen where pencil was required.whole paper
20. −1Diagram not redrawn for the sub-part that needed it.whole paper
21. −1Formula not stated before substitution (×2 instances).whole paper
22. −1Answer left in calculator-screen form (14.40000).whole paper
23. −1No conclusion statement linking working to the question.whole paper
24. −1Crossed-out working scribbled, not single-line struck.whole paper